Q What are the symptoms of aquilegia downy mildew?
A Affected leaves develop angular, yellow patches and start to curl and turn brown. A fine whitish-purple fungal growth may be visible underneath. Plants lose vigour and their flowers often become distorted and look water-soaked, with the stalks developing purple blotches. Seed pods can develop brown patches and fail to set seed. Badly affected plants can die.
Caption: Affected plants fail to thrive
Q How do I control aquilegia downy mildew?
A Check plants regularly and dispose of affected plants promptly; don’t compost them. Affected borders should be rested for at least a year. Buy only good-quality plants or grow your own from seed, which is currently thought to be lower risk. Avoid excessive use of high-nitrogen fertilisers and thin crowded plantings to improve air movement. Fungicides containing trifloxystrobin may also give some control if applied as soon as the disease is seen.
Q When did aquilegia downy mildew arrive in the UK?
A It was first seen in UK gardens in 2013, although the Food and Environmental Research Agency (Fera) had been aware of the problem since about 2011.
Currently it's mainly affecting southern England, although symptoms were seen on plants in Yorkshire recently, and it has become more widespread. Currently it's just aquilegia that's affected. In favourable conditions, it can spread quickly.
Q What's the outlook for the future?
A The disease may continue to spread, particularly if recent warm, damp weather patterns are repeated, so vigilance and prompt control of it are especially important. Large plantings are likely to be most at risk, particularly if dense and overcrowded.